Format decimal to two places or a whole number

Question

For 10 I want 10 and not 10.00 For 10.11 I want 10.11

Is this possible without code? i.e. by specifying a format string alone simlar to {0:N2}

Solution 1

decimal num = 10.11M;

Console.WriteLine( num.ToString( "0.##" ) );

Solution 2

It seems to me that the decimal precision is intrinsic to the decimal type, which defaults to 4 decimal places. If I use the following code:

decimal value = 8.3475M;
Console.WriteLine(value);
decimal newValue = decimal.Round(value, 2);
Console.WriteLine(newValue);

The output is:

8.3475
8.35

Comments

[Dave Bish]

This doesn't work - decimal num = 10.1; The best I can come up with is: num .ToString("C").Replace(".00", ""); Anyone who has the answer for this case would be helping me!

[tvanfosson]

@Dave - what doesn't work? Is it that you want exactly 2 decimals unless they are zero?

[tvanfosson]

@Dave - How about num % 1 == 0 ? num.ToString("0") : num.ToString("0.00"); You could implement it as an extension method on decimal.

[Microsoft Developer]

Console.WriteLine( num.ToString( "0.00" ) ); forces 2 DP even if the value is zero. i..e "0.00" or "0.10" etc. Don't forget default behavior is to round up from .005 not down.

[tvanfosson]

@dotNETNinja that's what Dave was asking for. In retrospect I might do decimal.Truncate(num) == num instead of mod by 1, though.

[Radu Simionescu]

this worked for me under mono... if you really have to use string operations to get this right, don't forget string.trimRight(new char[]{'0'}) to trim any trailing zeros - but do check that there is a decimal separator first

[Andrew]

I think this doesn't answer what Neil asked.